我如何打印(到控制台)的Id,标题,名称等,这个结构在Golang?

type Project struct {
    Id      int64   `json:"project_id"`
    Title   string  `json:"title"`
    Name    string  `json:"name"`
    Data    Data    `json:"data"`
    Commits Commits `json:"commits"`
}

当前回答

当你有更复杂的结构时,你可能需要在打印之前转换成JSON:

// Convert structs to JSON.
data, err := json.Marshal(myComplexStruct)
fmt.Printf("%s\n", data)

来源:https://gist.github.com/tetsuok/4942960

其他回答

有时,将结构体打印为有效的Go代码(相当于Go /ast代码)可能会很方便。出于这个目的,https://github.com/hexops/valast做得很好:

package main

import (
    "fmt"

    "github.com/hexops/valast"
)

type ProjectData struct {
    Title   string `json:"title"`
    Name    string `json:"name"`
    Data    string `json:"data"`
    Commits string `json:"commits"`
}

type Project struct {
    Id   int64        `json:"project_id"`
    Data *ProjectData `json:"data"`
}

func main() {
    p := Project{
        Id: 1,
        Data: &ProjectData{
            Title:   "Test",
            Name:    "Mihai",
            Data:    "Some data",
            Commits: "Test Message",
        },
    }
    fmt.Println(valast.String(p))
}

输出:

go run main.go 
Project{Id: 1, Data: &ProjectData{
        Title:   "Test",
        Name:    "Mihai",
        Data:    "Some data",
        Commits: "Test Message",
}}

我想推荐Go -spew,根据他们的github“为Go数据结构实现了一个深度漂亮的打印机,以帮助调试”

go get -u github.com/davecgh/go-spew/spew

使用的例子:

package main

import (
    "github.com/davecgh/go-spew/spew"
)

type Project struct {
    Id      int64  `json:"project_id"`
    Title   string `json:"title"`
    Name    string `json:"name"`
    Data    string `json:"data"`
    Commits string `json:"commits"`
}

func main() {

    o := Project{Name: "hello", Title: "world"}
    spew.Dump(o)
}

输出:

(main.Project) {
 Id: (int64) 0,
 Title: (string) (len=5) "world",
 Name: (string) (len=5) "hello",
 Data: (string) "",
 Commits: (string) ""
}

访问这里查看完整的代码。在这里你还可以找到一个在线终端的链接,在那里可以运行完整的代码,程序表示如何提取结构的信息(字段的名称、类型和值)。下面是只打印字段名的程序片段。

package main

import "fmt"
import "reflect"

func main() {
    type Book struct {
        Id    int
        Name  string
        Title string
    }

    book := Book{1, "Let us C", "Enjoy programming with practice"}
    e := reflect.ValueOf(&book).Elem()

    for i := 0; i < e.NumField(); i++ {
        fieldName := e.Type().Field(i).Name
        fmt.Printf("%v\n", fieldName)
    }
}

/*
Id
Name
Title
*/

您可以先执行json mashal并将其作为字符串打印。你可以看到整个struct的值。

package main

import "fmt"
import "json"

type Project struct {
    Id int64 `json:"project_id"`
    Title string `json:"title"`
    Name string `json:"name"`
}

func main() {
    o := Project{Id: 4, Name: "hello", Title: "world"}
    om, _ := json.marshal(o)
    log.Printf("%s\n", string(om))
}

一个简单的问题有很多答案。我还不如参加竞选呢。

package main

import "fmt"

type Project struct {
    Id    int64  `json:"project_id"`
    Title string `json:"title"`
    Name  string `json:"name"`
    //Data    Data    `json:"data"`
    //Commits Commits `json:"commits"`
}

var (
    Testy Project
)

func dump_project(foo Project) {
    fmt.Println("== Dump Project Struct ====")
    fmt.Printf("Id: %d\n", foo.Id)
    fmt.Println("Title: ", foo.Title)
    fmt.Printf("Name: %v\n", foo.Name)
}

func main() {
    fmt.Println("hello from go")
    Testy.Id = 3
    Testy.Title = "yo"
    Testy.Name = "my name"
    fmt.Println(Testy)
    dump_project(Testy)
}

输出的各种打印方法

hello from go
{3 yo my name}
== Dump Project Struct ====
Id: 3
Title:  yo
Name: my name